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  • Life and Medical Sciences  (5)
  • Organic Chemistry  (4)
  • Coronary arteries  (3)
  • 1
    ISSN: 1279-8517
    Keywords: Coronary arteries ; Coronary patterns ; Cardiac morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé La classification en dominance artérielle coronaire, actuellement utilisée (Schlesinger, Baroldi, Gensini) ne donne pas toutes les informations nécessaires à une bonne systématisation de la distribution des artères coronaires. Nous présentons ici une classification alternative, basée sur la segmentation des parois du ventricule gauche à la manière de Selvester. 1080 segments ventriculaires gauches de 90 coeurs humains prélevés sur des sujets de 4 jours à 94 ans ont été analysés en utilisant les techniques de microdissection. La présente classification est basée sur — la prédominance de segments irrigués par l'artère interventriculaire antérieure (IVA) : type I, par l'artère circonflexe (CX) : type II, — ou sur l'existence d'un équilibre entre ces deux artères : type III. Le pourcentage de distribution de ces groupes est le suivant : type I : 31 % ; type II : 37 % ; type III : 32 %. Chacun de ces groupes peut-être divisé en deux sous-groupes A et B selon — la prédominance du nombre de segments irrigués exclusivement ou en partage par l'IVA, — ou l'existence d'un équilibre entre l'IVA et la CX. Cette classification permet une approche plus réaliste du problème de dominance artérielle, étant donné que le ventricule gauche est toujours irrigué en prédominance par l'IVA, par la CX ou à la fois par les deux.
    Notes: Summary Nowadays, the classifications of coronary arterial preponderance (Schlesinger, Baroldi, Gensini) do not provide the necessary information for a good systematization of coronary arterial irrigation. Based on segmental analysis (Selvester's method) an alternative classification of the arterial distribution of the left ventricle is presented. One thousand eighty ventricle segments corresponding to 90 human hearts (age range from 4 days to 94 years) are studied, using microdissection techniques. In order to obtain segmental arterial patterns, a cluster analysis was used. The alternative classification is based on the predominance of the segments irrigated by: the anterior interventricular artery (Type I; 31% of cases), the circumflex artery (Type II; 37% of cases), or a balance between both arteries (Type III; 32% of cases). Each group can be divided into two subgroups (A and B), according to the existence or not of a balance between the territories of anterior interventricular and circumflex arteries. This classification allows as a more realistic approach to the subject of arterial dominance, given that the left ventricle always presents a predominant irrigation from the anterior interventricular, the circumflex or both arteries.
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  • 2
    ISSN: 1279-8517
    Keywords: Coronary arteries ; Coronary patterns ; Cardiac morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Sur une série de 90 coeurs, prélevés chez des sujets âgés de 4 jours à 94 ans (X=61,09±21,96) la distribution artérielle coronaire du ventricule gauche (VG) a été étudiée, en utilisant la classification des segments de Selvester, par angiographie post-mortem et microdissection. L'analyse des 12 segments du VG montre que les trois segments septaux (basal, médial et apical) présentent un type d'irrigation pratiquement constant, le type dual. Les segments supéro-apical, postéro-basal et postéro-mésial ont un indice élevé d'exclusivité pour les artères interventriculaire antérieure (IVA) et circonflexe (CX). Pour les autres segments, la vascularisation est de type mixte, quoique les segments apicaux présentent un haut degré d'exclusivité. L'analyse par segments du VG nous permet de conclure que la vascularisation artérielle de ce ventricule dépend fondamentalement de l'IVA et de la CX. Le petit apport de la coronaire droite (CD) est toujours mineur en regard de celui de la coronaire gauche.
    Notes: Summary In a series of 90 human hearts, from individuals aged between 4 days and 94 years (X=61.09±21.96) the coronary arterial distribution of the left ventricle (LV) was studied using Selvester's system of segmentation[24]. Postmortem angiographies and micro-dissection techniques were used. The analysis of the 12 segments of the LV showed that the three septal segments (basal, mesial and apical) present a type of irrigation which is practically constant and of a dual type. The superoapical, posterobasal and posteromesial segments present an irrigation with a high index of exclusivity for the anterior interventricular and circumflex arteries. In the rest of the segments the vascularization is of a mixed type, although the apical segments reach an important degree of arterial exclusivity. The analysis by segments of the LV allows us to conclude that the arterial vascularization of the left ventricle depends fundamentally on the anterior interventricular artery and the left circumflex artery, which are those that present the greatest extension, together with a small contribution by the right coronary artery, which is always minor with respect to the left coronary artery.
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  • 3
    ISSN: 1279-8517
    Keywords: Coronary arteries ; Coronary patterns ; Myocardial perfusion ; Left ventricle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé 90 coeurs humains issus d'autopsies ont été utilisés. Les méthodes utilisées furent l'angiographie post-mortem, la dissection et la cartographie artérielle par segments, selon la classification de Selvester et al. De l'ensemble de la série, on peut conclure que les artères qui ont la plus grande extension sont l'a. interventriculaire antérieure et l'a. circonflexe, tandis qu'elle est modérée pour l'a. coronaire droite, sauf dans les segments de la paroi inférieure. Des différences ont été trouvées dans les territoires de perfusion des artères coronaires principales, entre les types d'irrigation artérielle du ventricule gauche (type segmentaire et type groupé). Finalement, nous définissons des groupes à risques sur la base de la proportion de masse ventriculaire irriguée par chaque artère, ce qui pourrait être d'un intérêt pratique du point de vue clinique, pronostique et thérapeutique.
    Notes: Summary Ninety human hearts obtained from autopsies were used. The methods applied were post-mortem angiography, dissection and the construction of an arterial map by segments, according to the classification of Selvester et al. It was shown that the arteries which have the greatest extension are the anterior interventricular and circumflex aa., while irrigation by the right coronary artery is only moderate, except in the segments of the inferior wall. Differences in the perfusion territories of the main coronary arteries and between the patterns of arterial irrigation of the left ventricle (segmental pattern and grouped pattern) were found. Finally, we define risk groups on the basis of the proportion of the ventricular mass irrigated by each artery, which are of practical interest from the clinical, prognostic and therapeutic points of view.
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  • 4
    ISSN: 0897-3806
    Keywords: myocardium ; transcoronary ablation ; anterior interventricular artery ; Life and Medical Sciences ; Miscellaneous Medical
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The aim of this study is to determine the anatomical explanation for the greater or lesser vulnerabilities of the left ventricular segments in the event of occlusion of each of the main coronary arteries. To this end, we analyzed the arterial perfusion of 1,080 left ventricular segments from 90 human hearts obtained at autopsy. Post-mortem angiography, dissection, and constriction of an arterial map using the classification of Selvester et al. (1982) were applied. By careful monitoring of the arterial perfusion of each segment we conclude that (1) obstruction of the anterior interventricular artery (AIV) especially affects the superomesial, superoapical, and anteroapical segments; (2) obstruction of the circumflex artery (CX) especially affects the posterobasal and posteromesial segments; and (3) obstruction of the right coronary artery (RC) especially affects the inferobasal and inferomesial segments. Vulnerability of the myocardially segments decreases in those segments which have collateral supply, i.e., those which are only relatively dependent upon a particular coronary artery. © 1994 Wiley-Liss, Inc.
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  • 5
    ISSN: 0730-2312
    Keywords: monoclonal antibody DWP ; activated ras protein reactive antibody ; anti-ras antibodies ; anti-ras monoclonal antibody ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Activated ras transforming genes have been described in a variety of neoplasms and encode 21,000-Dalton (p21) proteins with amino acid substitutions at positions 12, 13, and 61. In this report we describe a monoclonal antibody designated DWP that reacts. Specifically with synthetic dodecapeptides containing valine at position 12, to a lesser extent with peptides containing cysteine at position 12 and not with peptides containing glycine, arginine, serine, aspartic acid, glutamic acid or alanine at the same position. Western blot and immunoperoxidase studies showed that DWP specifically reacts with activated rasH or rasK proteins in NIH cells transformed by DNA from the human carcinoma cells that encode valine at position 12. DWP did not react with normal p21s encoding glycine at position 12, nor with activated p21s encoding aspartic acid, glutamic acid, arginine, serine, or cysteine at position 12. A survey of human tumor cell lines demonstrated that DWP reacted with the human bladder carcinoma cell line T24 but not with human tumor cell lines previously shown td contain other activating mutations at positions 12 or 61. DWP and perhaps additional antibodies that specifically react with alterations at positions 12 or 61 of the ras protein may be valuable in determining the presence and frequency of activated ras proteins in human malignancy.
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  • 6
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Development of ciliated (CC) in the fetal human trachea was studied by light and electron microscopy in specimens obtained from 45 embryos or fetuses aged from 9 to 27 weeks of gestation (menstrual age). Four stages could be recognized during tracheal development. Up to 11 weeks (stage I), the trachea was covered with a columnar undifferentiated epithelium with abundant glycogen, apical microvilli, and primary cilia. From 12 to 18-19 weeks (stage II), centriolo-genesis and secondary ciliogenesis were very active, and the percentage of CC and secretory cells (SC) progressively increased. From 20 to 22-23 weeks, the density of CC was higher but, in parallel, the percentage of SC decreased (stage III). Throughout this period, the different steps of ciliogenesis could be identified in the same field, and the ciliated borders consisted of ciliary shafts with a disorderly arrangement. Megacilia were identified. Some of the preciliated cells had both cilia and secretory granules in their apical cytoplasm. After 24 weeks (stage IV), the ciliated border was apparently mature, the rootlets lengthened, and the cilia were correctly orientated. Whatever the fetal age, the density of CC was significantly higher (P 〈 .01) in the dorsal trachea compared to the ventral trachea. There are many similarities between animal and human ciliogenesis, but in human fetuses, most of the ciliary differentiation occurs early, during the first half of gestation. As demonstrated in experimental models, SC likely play a major role in genesis of CC during the fetal development of the human trachea.
    Additional Material: 12 Ill.
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  • 7
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A study of the isthmus and ligament in unionid mussels was undertaken employing methods specifically designed to preserve the in vivo relationships of these interrelated structures. Serial sections of the hard and soft tissues were used for two-dimensional analysis. From these, a tridimensional computerized reconstruction was developed. Special dissections of the undisturbed isthmus were also utilized. By using such methodologies, a new description of the ligament has been developed employing such terminology as the foliated ligament and the posterior folding laminae. Similarly, for the isthmus, an anterior lyre, a pallial crest, a pallial peduncle, and a posterior lyre are described. Such entities are both morphologically and physiologically related to the shell and ligament.
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  • 8
    ISSN: 0749-503X
    Keywords: Heterologous gene expression ; levansucrase precursor ; Bacillus subtilis ; yeast ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Levansucrase, a Bacillus subtilis extracellular enzyme, was not secreted in the culture medium when produced in yeast. The protein accumulated inside the cell in its precursor form which represented 0·3% of total proteins. The absence of any post-translational modifications, such as signal sequence cleavage or addition of N-linked sugars, indicated that this protein did not enter the reticulum secretion pathway.Direct observation of the cells by confocal laser scanning microscopy showed that levansucrase was associated with the cytoplasmic membrane. Subcellular fractionation experiments revealed that levansucrase precursor form is associated with membranes through weak ionic interactions. The purified precursor displayed the same catalytic properties as levansucrase secreted by B. subtilis. Thus yeast could be used as a source of levansucrase precursor allowing its isolation as a pure form on a milligram scale.
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  • 9
    ISSN: 0899-0042
    Keywords: solvent ; basic medium ; competitive solubilities ; optimization ; optical resolution ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several preparative resolutions of 5,5-disubstituted hydantoins have been achieved via fractional crystallization of diastereoisomeric salts. The process can be extended by making use of the difference between the variation of solubilities of the hydantoins and their salts with α-methylbenzylamine as a function of the alkalinity of the medium. Optimization for each resolution procedure involves a refinement of the excess amount of base needed. © 1992 Wiley-Liss, Inc.
    Additional Material: 2 Ill.
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  • 10
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of Phenyldiazomethane with 1,3-Thiazole-5(4H)-thiones: Base-Catalyzed Ring Opening of the Primary AdductReaction of 1,3-thiazole-5(4H)-thiones 1 and phenyldiazomethane (2a) in toluene at room temperature yields the thiiranes trans- and cis-1,4-dithia-6-azaspiro[2.4]hept-5-enes (trans- and cis-4; Scheme 2). With Ph3P in THF at 70°, these thiiranes are transformed stereospecifically into (E)- and (Z)-5-benzylidene-4,5-dihydro-1,3-thiazoles 5, respectively. In the presence of DBU, 1 and 2a react to give 1,3,4-thiadiazole derivatives 6 or 7 via base-catalyzed ring opening of the primary cycloadduct (Scheme 3). In the case of 2-(alkylthio)-substituted 1,3-thiazole-5(4H)-thiones 1c and 1d, this ring opening proceeds by elimination of the corresponding alkylthiolate, yielding isothiocyanate 7. The structures of (Z)-5c and 6b have been established by X-ray crystallography.
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